Sitting for Extended Periods Raises Heart Disease Risk, Regardless of Physical Activity Levels
We know staying active is healthier than being sedentary, but new research finds that too much sitting—regardless of exercise—is hard on the heart.
Fitting in a workout after a long day at a desk may not sufficiently counteract the harmful effects of sedentary behavior on heart health, according to a new study from Mass General Brigham.
The study, published Friday in the Journal of the American College of Cardiology, found that excessive sedentary behavior, which researchers defined as waking activity with low energy expenditure while an individual is sitting, reclining, or lying down, is linked to an increased risk of heart disease, particularly heart failure and cardiovascular death.
Activity Levels Also Associated With Sleep Levels
“Many of us spend the majority of our waking day sitting, and while there’s a lot of research supporting the importance of physical activity, we knew relatively little about the potential consequences of sitting too much beyond a vague awareness that it might be harmful,” lead study author Dr. Ezimamaka Ajufo, a cardiology fellow at Brigham and Women’s Hospital, stated in a press release.
The researchers examined the relationship between daily sitting time and future risk of four common cardiovascular diseases: atrial fibrillation, heart attack, heart failure, and cardiovascular death. They classified sedentary behavior using a machine learning algorithm.
- More than 10.6 sedentary hours per day
- 9.4 to 10.6 sedentary hours per day
- 8.2 to 9.4 sedentary hours per day
- Less than 8.2 sedentary hours per day
Those spending the least time sitting not only showed the most active time but also slept the most. Similarly, participants who spent the most time sitting, besides being the least active, slept the least.
5 Percent of Participants Developed Atrial Fibrillation
After follow-up over an average of eight years, about 5 percent of study participants developed atrial fibrillation, about 2 percent developed heart failure, nearly 2 percent experienced a heart attack, and roughly 1 percent died from cardiovascular-related causes.
“Sedentary risk remained even in people who were physically active, which is important because many of us sit a lot and think that if we can get out at the end of the day and do some exercise we can counterbalance it. However, we found it to be more complex than that,” Ajufo stated in the press release.
The researchers’ analysis found that sedentary behavior was associated with a higher risk of all four types of heart disease, with a 40 percent to 60 percent greater risk of heart failure and cardiovascular death observed when sedentary behavior exceeded 10.6 hours a day (excluding hours spent sleeping).
Adverse Effects Persisted Despite Exercise
The latest Physical Activity Guidelines for Americans recommend adults perform at least 75 to 150 minutes of vigorous aerobic activity, or 150 to 300 minutes of moderately intense aerobic activity, every week, along with two days of strengthening exercises.
Notably, many adverse effects persisted even among those who met the recommended physical activity levels.
“Our data supports the idea that it is always better to sit less and move more to reduce heart disease risk, and that avoiding excessive sitting is especially important for lowering risk of heart failure and cardiovascular death,” co-senior study author and electrophysiologist Dr. Shaan Khurshid said in the press release.
The authors plan to expand their research to study how sedentary behavior relates to other diseases over more extended periods.
The research team hopes their findings will inform public health guidelines. They also expressed interest in prospective studies investigating the effects of interventions designed to reduce sedentary behavior and their impact on cardiovascular health.
“Exercise is critical, but avoiding excessive sitting appears separately important,“ co-senior author and cardiologist Dr. Patrick Ellinor said in the press statement. ”Our hope is that this work can empower patients and providers by offering another way to leverage movement behaviors to improve cardiovascular health.”